Automatic heat regulator



1366- 1933 E. l. DAVIS ET AL AUTOMATIC HEAT REGULATOR Filed June 9, 1952 2 Sheets-Sheet 1 3 [NI ED27 035? JYJ fl z aw flTTORNEI.

Dec. 19, E DAVlS E AL 1,940,119

AUTOMATIC HEAT REGULATOR Filed June 9, 1952 2 Sheets-Sheet 2 1 753. INVI'JVTOEJ1' 7/ f %lmd my Patented Dec. 19, 1933 PATENT OFFICE A AUTOMATIC HEAT REGULATOR Ervy I. Davis and Charles E. Pearson, St. Paul, Minn.; said Pearson assignor to said Davis Application June 9, 1932. Serial No. 616,216

. 3 Claims.

Our invention relates to an automatic draft regulator and heat control device for furnaces, particularly so-called hot air furnaces.

The main object is to provide a highly eflicient device controlled by room temperatures and furnace heat conditions. It embodies an electrically controlled motor operating a blower or fan which circulatesheat to the rooms, the latter type of fan being preferably such as disclosed in our patent application Serial No. 445,064, allowed April 22, 1932, for furnace heat circulator.

j Further objects of our invention and preferred embodiments of its construction in detail are hereinafter fully disclosed reference being had to the accompanying drawings, in which-- Fig. 1 is a side elevation of a hot-air furnace with our improved regulator inoperative connection therewith. Fig. 2 is a sectional detail view. of the lower part of Fig. 1 about as on line 2--2. Fig. 3 is an enlarged detail view about as on line 33 in Fig. 2. Fig. 4 is a side elevation in enlarged scale of a thermostatic control device and Fig. 5 is a face view of Fig. 4 with electric circuit diagram added.

Referring to the drawings by reference nu-, merals, 6 designates a hot-air furnace having a smoke flue '7 with hinged check lid 8. 9 is the usual draft door lid at the lower front part. This type of furnace comprises an inner fire or heating chamber (not shown) concentric of which is set the outer shell 6 and providing between them an encircling heating space 10 (see Fig. 2) from which heat is suitably conducted by pipes to various rooms, as above the floor f (Fig. 1).

11 is a box-like housing at the lower part of the furnace in which is rotatably mounted a fan shaft 12 carrying a blade fan 13 which draws cooled air from the lower interiorof the furnace and blows it upwardly with considerable velocity at a higher elevation to and through the usual pipes as 61 leading to various rooms. The direction of the air currents is designated by arrow .14inFig. 2.

An object of this invention, further, is to provide anautomatically acting means which will end of the fan shaft 12 which isv parallel to and below the motor shaft. 69

Within the main pump-housing 15 is suitably fixed acorrespondingly shaped reservoir 2lzthe side walls and bottom of which are spaced inwardly of the sides and bottom of the housing (see Fig. 3). 22 is a tight fitting lid for housing 15 and which also closes the top of the reservoir. 23 is an upwardly open float member reciprocablevertically within the upper half or more of the, reservoir and guided by an upright rod 24 rigid1y fixed to the float and extending upwardly through an aperture 22A in the lid, the rod extending always therethrough and its upper end withan eye 24E or other suitable means for connecting itto a flexible cord or wire 25. The cord 25 has direct connection with the check 76 lid 8 and connected other cords actuating the draft lid 9, said cords also connected'by flexible actuating means to athermostatic control devicedesignated B in Fig. 1 and all said flexible control draft and check means herein presently to be fully described. Referring particularly to Fig. 1, cord 25 extends first upwardly thence from a pulley or sheave 26 horizontally to another sheave 27 and thence downto and connected at '28 with the free edge part of check lid 8, 29 being a weight on the cord which keeps it taut and tending to keep lid 8 closed. From point 30 on cord 25 another cord 31 extends to and over a sheave 32 thence down to and connected at 33 to draft lid 9. Cords 25 and 31 are of such lengths that when lid 8 is closed .draft lid 9 isopen and vice versa. 34 is a counteris closed and cord 25 is maintaining rod 24 and its float 23 in lowered position. And when check 8 is closed, draft 9 is open at which time the float 23 is raised (see full lines 23 in Fig. 3) the fire in the furnace picks up. During the latter condition electric circuit is closed causing rotation of the motor 17 and the fan 13 causes forced circulation of heat to the rooms. This closed circuit is started and maintained by the thermostat B which has a fixed circuit contact 36 and a flexible metal leaf contact 3'? therebelow, both connected, to circuit wires 38 and39, current being taken from any suitable source 40. The leaf contact is pivotally mounted as at 41 and is oscillatable in a vertical plane and provided with an auxiliary arm 110 42 with a downward directed tooth 42T arranged to move into or out of contact with a toothed arcuate rack disc 43D comprising an integral part of a pulley 43. Above the leaf 3'? is mounted a series of connected and vertically oscillatable wafers 44 sensitive to temperature changes. A horizontal bar 45 below the lowest wafers and rigidly connected thereto, carries a contact roller 46 arranged to press leaf 37 down when the wafers expand. When the room temperature.

goes down the wafers contract, leaf 37 bears upwardly until it contacts with 36, closing circuit and starting the motor and fan. Simultaneously tooth 42T is disengaged from the ratchet 43D and weight 29 at the check lid causes closing of said lid (8) pulling cord and another cord 4'? the function of which will now be described. Said cord 4'7 is secured at one end at point on cord 25, extends thence, suitably guided through floor F and over sheave 43 of the ther mostat, thence down, as 47A Fig. 1, and its other end secured at 48 to a counterweight cord 49 con nected to cord 25 just above bar 24. In Figs. 4 and 5 cord 47 is shown as a chain.

Assuming now that the furnace 6 has a gradually decreasing or cooling fire and that the parts of our regulator are in operative positions shown in Fig. 1 (float 23 in lowest position shown dotted in Fig. 3). The following description of operation is in order. As the furnace heat decreases room temperatures fall and the thermostat closes circuit, motor 1'? goes into action and fan 13 is rotated. 50 is a centrifugal pump on the end shaft 12 opposite the motor and is within the upper open end of the float.

. its-bottom smaller than the duct opening.

because of slack in cord 31.

within a pump housing 51 fixed to the adjacent wall of the reservoir 21. 52 is an outlet duct from the pump opening inwardly and downwardly in inclined plane with its outlet being 53 'designates a volume of oil in the reservoir. As the motor rotates the pump is set in action, pumping oil through duct 52 and discharging it in the float 23, the latter having an outlet 35 in Obviously the oil that is pumped into the float will weight it down gradually although the outlet 35 permits slow circulation of oil out of the float as the oil tends to maintaina level. The accumulating oil discharged into the float will cause the later to descend until stopped by contact with the stationary tubular housing 54 of shaft 12. 55 and 56 designate respectively an inner flanged bushing on shaft 12 where it gos through the wall of the reservoir and the outer bushing fixed in casing 15. The downward gradual movement-of the float, as above described, exerts immediate pull on cord 25 (through bar 24) the pull on cord 25 causing action which raises lid 8 and simultaneously the draft lid is closed Thus after a certain period of time required for the float to descend the draft is gradually closed and the check gradually opened and the generated furnace heat is simultaneously and continously circulated by the fan into the rooms. Obviously the pull on cord 25 eases cord 47 causing the pulley 43 and ratchet disc 43D to rotate anti-clockwise. Fan 13 continues to operate even after draft is closed until the thermostatic control device breaks circuit, when the heat sensitive wafers 44 expand. Simultaneously with the latter movement the tooth 42T engages in the arcuate toothed rack 43D and cord 47 is inoperative.

In Figs. 1 and 5, 57 designates a heat regulator thermostat of the type well known in the art action of weight 29.

and mounted to contact with the furnace shell. This device may be used in conjunction with our control device to set the fan and draft operating means in action. Such device is merely included in the circuit 38-39 (Fig. 5) it being understood that this device makes and breaks circuit according to furnace temperature instead of being made operatable or effective by room temperatures.

When the float 23 has been lowered by the action above described and pumping of oil ceases the oil attains its level circulating through aperture 35 and the float is automatically restored to raised position (as in Fig. 3) primarily by the action of a counterweight 60, aided by the The float 23 is heavier than the weight 60. Weight 29 is of course ineffective as long as cord'4'7 cannot ease as the latter is also inoperative until ratchet 43 is released by tooth 42T when circuit is closed. In other words the float 23 remains lowered, check lid 8 open and draft lid 9 closed until room temperature lowers sufficiently to operate the device by closing circuit. When this takes place the draft is opened the check closed and float 23 is raised to upper position.

In Fig. 3, 59 designates an oil retrieving duct with one end in the chamber C below the reservoir, the other end of said duct located at the intake of the, oil pump. Suction of the pump draws any oil there may be in chamber C into the reservoir. Said duct 59 merely keeps the chamber drained of any oil which may seep or pass through at bearing 55 and drips off of shaft 61 designates a hot air pipe from the furnace to a room and 62 is an outlet register in the room.

Our invention and its operation have now been fully disclosed. A number of modifications such as details of structure and proportions of various parts may be embodied without departing from the scope and spirit of the invention.

We claim:

1. A heat-regulator device for hot-air furnaces having a rotary blower for circulating heat generated in the furnace through ducts to various rooms; said regulator comprising an electric motor operatively connected with said blower, a thermostat, a series of flexible cord means operatively connected with the check lid of the furnace and the draft lid of the furnace, an electric circuit and automatic circuit closing and opening means operated by said thermostat to cause starting and stopping of the motor and blower, a float chamber mounted in proximity to the motor, a float in said chamber adaptable for vertical oscillating movement, direct connection means for said float with the flexible cord means and the latter arranged to be pulled or slackened suc- 1 cessively by the oscillating movement of the float to regulate said check and draft lids simultaneously, a fixed reservoir mounted in said chamber, a volume of liquid therein'and in the chamber and the float oscillatable vertically in said reservoir, said float open upwardly, a centrifugal pump in the lower part of said chamber and rotatably connected to the motor, a housing for said pump member and a duct extending therefrom to conduct pumped liquid into the open end of the float, said float provided with an aperture in its bottom smaller than the outlet of the said-duct, and said float member guided to descend gradually when liquidis pumped thereinto, said flexible cord means directly connected to the float to cause the draft-lid of the furnace.

2. In a hot-air furnace regulator of the class described, an electric circuit, dual thermostatic control means and an electric motor in said circuit, one thermostat mounted in a room remote from the furnace and the other comprising an electric furnace regulator and both arranged to automatically close and open circuit to the motor, a rotary fan having operative connection with said motor and adapted to cause forced circulation of heated air from the furnace through suitable ducts, a float chamber mounted near the motor, a pump within said chamber directly connected with the motor shaft, a liquid reservoir comprising said chamber, said pump arranged to forcibly feed liquid into the float to weight it and cause descent of the float in the liquid, flexible cord means connected with said float and with the draft and check means of the furnace, a counterweight in said cord means arranged to cause raising of the float when the pump action stops.

3. The structure specified in claim 2, in which said float reservoir is mounted rigidly within the chamber, with, the walls and bottom in spaced relation to the walls and bottom of the chamber,

a flexible coupling connection between the motor shaft and the pump shaft exteriorly of the said chamber, and secondary duct means within the chamber comprising a tube communicating with the space between the adjacent bottoms of the reservoir and the chamber and its other end located in the intake part of the pump, for the purpose set forth.

CHARLES E. PEARSON.

ERVY I. DAVIS. 

